Film-processing tank

ABSTRACT

A tank for processing filmlike material that is transported through discrete sections of the tank in looped configuration. Each tank section is provided with a discrete weighted roller, that differs in weight or buoyancy from the other rollers, and each of which ride in guide rails to carry the material into the tank sections. The material is confined by the rollers in its passage through the several sections.

United States Patent Inventor Seymour L. Hersh Freehold, NJ. Appi. No.830,069 Filed June 3, 1969 Patented Aug. 31, 1971 Assignee The UnitedStates of America as represented by the Secretary of the ArmyFILM-PROCESSING TANK 2 Claims, 5 Drawing Figs.

U.S. CL 95/94 R, 95/89 R, 68/175, 1 18/423 Int. (11 G03d 3/00 FieldofSear-ch 95/89, 89 A, 94; 226/189; 68/175; 118/423-425 References CitedUNITED STATES PATENTS 7/1921 Sentou 95/94 1,602,600 11/1926 Webb 226/189X 1,946,841 2/1934 Ybarrondo 95/94 1,967,889 7/1934 Kitroser.... 95/942,445,504 7/1948 Williams... 95/94 UX 2,555,673 6/1951 Beatty 118/423 XFOREIGN PATENTS 611,127 3/1927 France 95/94 Primary Emininer-lohn M.Horan Assistant Examiner-Alan Mathews Attorneys-Harry M. Saragovitz,Edward J. Kelly, Herbert Berl and Milton M. Davis ABSTRACT: A tank forprocessing filmlike material that is transported through discretesections of the tank in looped configuration. Each tank section isprovided with a discrete weighted roller, that differs in weight orbuoyancy from the other rollers, and each of which ride in guide railsto carry the material into the tank sections. The material is confinedby the rollers in its passage through the several sections.

PATENTEB AUBS 1 IHYI INVENTIOR. SEYMOUR L.. HERSH ATTORNEYS IhtLM-PIROQESSING TANK The invention described herein may bemanufactured, used,

, and licensed by or for the U.S. Government for governmental purposeswithout the payment to me of any royalty thereon.

BACKGROUND OF THE INVENTION The present invention relates generally to atank for treating and processing web or filmlike sheets of material inlooped like configuration and more specifically to a tank of the kinddescribed for processing photographic film. Such processing tanks areconventionally divided to include respective developing, fixing, washingand drying compartments. Such tank system is placed between a feed reeland a takeup reel and the film is transported in a looped patternthrough the several compartments.

In such tank systems, standard photographic film processing required theuse of substantial amounts of leader to thread up or dress the machineprior to the actual start of film processing. This leader must beattached by splicing or taping to the film, usually in darkness whichrequires considerable time to accomplish. Furthermore, the leader isexpensive if discarded after use, which must be done if it is notcarefully washed.

Several design approaches have been proposed in the past to alleviatethis problem. Leaderless systems have been designed that utilize belts,tapes or a multiplicity of rollers to automatically transport the filmthrough the tank system. Such roller-type systems are complicated,subject to malfunction and are limited to fairly stiff material thatwill not flex or lose their path of travel in the complex roller system.Some film transport systems include a complex cam-actuated, loopformingmeans. Such an automatic system utilizes a preset schedule for formingfree-hanging loops in each tank. After a loop is formed in the firsttank, a second drive roller meshes into operation which feeds film intoa second tank. This continues until all the required loops are formed,dependent upon the number of compartments in the system. Suchloop-forming system is complex requiring accurate design and control ofcomponents. A serious deficiency exists since the film has no lowerroller support permitting the film to twist, tangle and stick together.

SUMMARY OF THE INVENTION It is the general purpose of this invention toprovide a filmprocessing system for tank processing that includes amethod of forming loops by a series of rollers of varying weight whichtake up the slack formed by the feedout film from the supply reel.Control over the order in which the rollers descend into theirrespective compartments is determined by the weight of each roller ashereinafter described.

BRIEF DESCRIPTION OF THE DRAWING The exact nature of this invention willbe readily apparent from consideration of the following specificationrelating to the annexed drawing in which:

FIGS. .1-3 are schematic representations showing operational stages ofthe film-processing system; and

FIGS. 4a and 4b are views of the roller-locking means in open and lockedpositions respectively.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing, FIG. Ishows all the essential components of the film-processing system inaccordance with my invention. The system includes a tank II that isdivided into four compartments I3, 15, I7 and 19. Each of thecompartments l3, l and 17 have contained therein appropriate liquidsolutions for developing, fixing and washing. The fourth compartment ll9may serve as a dryer for the film in its final stage of processing.Adjacent to the left-hand end of the tank is a processed is showninitially at 25. Positioned slightly above the discrete tankcompartments 13-119 are spaced fixed idler rollers shown at 17-35 thatserve to position and guide the film in its travel during processing.The means for securing and the mounting of the rollers 27-35 is of noimport to the invention and therefor not shown in any detail.

Also positioned above the tank 11 are a series of longitudinally movablerollers shown at 37-43 each including a drive shaft, one of which isshown at 45. Each of the rollers 37-43 is so positioned that any one ofthe rollers lies between two adjacent idler rollers heretoforedescribed. Thus, for example, movable roller 39 lies between rollers 29and 31. The positioning of the movable rollers is such that each of saidrollers is substantially equidistant from the sides of each tankcompartment over which each is positioned. For positioning, guiding andconfining the rollers 37-43, each of the tank compartments is providedwith opposing guide rails 47 being affixed to opposing sidewalls of thecompartment. The guide rails 4'7 are designed to permit the shafts 45 ofthe movable rollers to ride therein. For confining the rollers 37-43 inthe lower part of each compartment as is shown in FIG. 3, there areprovided locking means shown at 49 in FIG. 4. The locking means includea pair of pivotable arms positioned adjacent the bottom end of the guiderails 47. The locking means are so designed as to engage and confine theshafts of the rollers but not so rigidly as to retard the free rotationof the rollers.

It has been determined that operation of the processing device hereindescribed could only be achieved if the movable rollers 37-43 are ofvarying weights in specific order. Accordingly, the roller 37 closest tothe supply reel Zll is the heaviest of the rollers and the rollers 39,41 and 43 decrease in weight in that order. In one specific design of afilm-processing system of the kind described herein the rollers had thefollowing weights:

roller 37 935 g. roller 39 823 g. roller 41 707 g. roller 43 632 g.

The operation of the film-processing system herein described issubstantially as follows:

Reference is made to FIG. 1 where it may be seen that the film 25, witha short portion leader attached thereto is positioned in a straight pathbetween the idler rollers 27-35 and the movable rollers 37-43, with thesupply reel and takeup reel locked. At this time the movable rollers arereleased from their temporary fixed position to rest upon the leaderportion of the film. Rotation of the feed roll 21 is initiated by adrive motor (not shown) at a predetermined governed speed. As the film25 is unwound from the feed reel and slack is formed, the roller 37 willbegin to descend into the compartment 13 carrying the slack film, asshown in FIG. 2. When the roller 37 reaches the bottom of the guiderails: 47, the locking arms 49 will loosely engirdle the shaft portionof the roller 37 and maintain it in such position close to the bottom ofthe compartment and still allow rotation of the roller. The film 23 isstill continuously fed from reel 21 at the same governed rate of speedat which time the movable roller 39 will begin its descent intocompartment 15 and film will be drawn over the idler roller 29. In thesame sequence the rollers 4ll and 43 will fall into their respectivecompartments l7 and 119. At such time all the movable rollers 37-43 arelocked in their respective positions as shown in FIG. 3. At such timethe takeup reel 23 is initially activated either manually or preferablymotor driven to draw the film through all its processing stages in theseveral compartments. The supply reel drive at this time may bedisengaged. After such processing, and all the film is on the takeupreel 23, the rollers 37-43 are retrieved from the lower portions of thetank compartments. Such retrieval may be accomplished by the use ofstrings or tapes that are secured to each end of the shaft of eachroller. Such lifting-action will upset the pivotable locking arms 49 toallow lifting of the rollers. Obviously such lifting force must begreater than that exerted when the film is normally drawn through theprocessing tank. In the specific description of the embodiment herein,the rollers 3743 are of successive lighter weight. While sucharrangement is preferable, it is obvious that other roller arrangementscan be utilized to accomplish the same ends. In one such arrangement theroller 37 would be hollow and open ended or provided with peripheralopenings to allow liquid to enter therein. Located medially within theroller is an evacuated chamber of a fixed length formed by sidewalls.The next roller 39 will also be provided with an evacuated chamber thatis slightly larger than the one in roller 37. In similar manner therollers 41 and 43 will include successively larger evacu- 'atedcompartments. By such arrangement each of the rollers will be slightlymore buoyant than the roller to its left as seen in FIG. 1. Thisarrangement will permit the rollers to descend in the same order as theweighted rollers heretofore described.

The processing system herein described lends itself to otherapplications where a continuous film or web of material must betransported through several liquid-filled treating tanks. Suchapplications may be in the arts of cloth treating and dyeing, papermanufacturing and the like.

We wish it to be understood that we do not desire to be limited to theexact details of construction shown and described, for obviousmodifications will occur to a person skilled in the art.

What is claimed is:

1. A system for processing a continuous strip material including a tankhaving a plurality of discrete compartments, each having an appropriatetreating agent therein,

feed and takeup means for said material positioned respectively atopposite ends of said tank,

a plurality of fixed rollers adjacent to the upper edge of said tank forguiding said material in its travel,

a plurality of movable rollers positioned above said tank 7 adapted todescend freely, individually and successively into each of saidcompartments as each of said rollers engage slack film released fromsaid feed means to form a U-shaped loop of said film within the severalcompartments,

means for retaining said movable rollers adjacent to the bottom of eachcompartment, said retaining means for each of said movable rollerscomprising a pair of opposing pivotable locking arms adapted tosubstantially engirdle the respective roller, and each of said movablerollers being of successive decreasing weight in the order from the feedmeans to the takeup means.

2. A tank assembly for processing continuous strip film comprising;

an open-top tank having several parallel vertical partitions that dividethe tank into hydraulically separate compartments, independentlylockable and independently drivable film feed and takeup meanspositioned outside of and at opposite ends of said tank such that thecompartments are in succession between the feed and takeup means, afixed guide roller positioned in the tank at each end thereof andprojecting above the respective end walls of the tank to guide film fromthe feed means into the tank and from the tank to the takeup means, afixed guide roller positioned in the tank above each partition,

opposing guide rails in each compartment along the sides of the tank,

a movable guide roller for each compartment, each including an axiallyextending shaft for registration with the opposing guide rails, theguide rollers for the successive compartments from the feed means end ofthe tank to the takeup means end of the tank being of progressively lessweight,

releasable guide-roller-retaining means adjacent the bottom end of atleast one of the opposing guide rails in each compartment for engagingthe respective guide roller shaft, whereby when the movable guiderollers are temporarily fixed in positions higher than the fixed guiderollers, film may be stretched from the feed means to the takeup meansbetween the movable guide rollers and the fixed guide rollers, the feedand takeup means fixed, the movable rollers released to rest upon thefilm and then the feed means released and driven until the movable guiderollers move downward to their respective retaining means in succession,at which time driving of the feed means may be terminated and driving ofthe takeup means begun.

1. A system for processing a continuous strip material including a tankhaving a plurality of discrete compartments, each having an appropriatetreating agent therein, feed and takeup means for said materialpositioned respectively at opposite ends of said tank, a plurality offixed rollers adjacent to the upper edge of said tank for guiding saidmaterial in its travel, a plurality of movable rollers positioned abovesaid tank adapted to descend freely, individually and successively intoeach of said compartments as each of said rollers engage slack filmreleased from said feed means to form a U-shaped loop of said filmwithin the several compartments, means for retaining said movablerollers adjacent to the bottom of each compartment, said retaining meansfor each of said movable rollers comprising a pair of opposing pivotablelocking arms adapted to substantially engirdle the respective roller,and each of said movable rollers being of successive decreasing weightin the order from the feed means to the takeup means.
 2. A tank assemblyfor processing continuous strip film comprising; an open-top tank havingseveral parallel vertical partitions that divide the tank intohydraulically separate compartments, independently lockable andindepeNdently drivable film feed and takeup means positioned outside ofand at opposite ends of said tank such that the compartments are insuccession between the feed and takeup means, a fixed guide rollerpositioned in the tank at each end thereof and projecting above therespective end walls of the tank to guide film from the feed means intothe tank and from the tank to the takeup means, a fixed guide rollerpositioned in the tank above each partition, opposing guide rails ineach compartment along the sides of the tank, a movable guide roller foreach compartment, each including an axially extending shaft forregistration with the opposing guide rails, the guide rollers for thesuccessive compartments from the feed means end of the tank to thetakeup means end of the tank being of progressively less weight,releasable guide-roller-retaining means adjacent the bottom end of atleast one of the opposing guide rails in each compartment for engagingthe respective guide roller shaft, whereby when the movable guiderollers are temporarily fixed in positions higher than the fixed guiderollers, film may be stretched from the feed means to the takeup meansbetween the movable guide rollers and the fixed guide rollers, the feedand takeup means fixed, the movable rollers released to rest upon thefilm and then the feed means released and driven until the movable guiderollers move downward to their respective retaining means in succession,at which time driving of the feed means may be terminated and driving ofthe takeup means begun.